But it was his health food restaurant bookkeeping that ultimately landed him in court.

Top House Republicans were blindsided Monday by a 20-count indictment, alleging the New York Republican violated tax laws and tried to cover it up. Republicans knew feds were sniffing around, but they didn’t foresee these charges.

But he’s holding on. None of them have called for Grimm’s resignation, even though this is the most serious alleged ethical problem they’ve encountered since regaining the majority. At this point, senior Republicans seem to be pushing a coordinated message that Grimm can stick around while the legal process plays out — which can take months.

House Speaker John Boehner’s conference — which came to power vowing zero tolerance on ethical missteps — is now saddled with an indicted lawmaker who will be nearly impossible to get off the ballot, shows no signs of resigning and could easily lose in November. House Republicans have had to deal with some members’ bad behavior during their three-plus years in power, but nothing like these allegations.

“With Michael Grimm, he’s going to have to make his case to his constituents and make his case in court,” House Majority Leader Eric Cantor (R-Va.) told POLITICO.

After returning to Capitol Hill on Tuesday, Grimm moved quickly to try to limit the political fallout. He needs to prevent a critical mass of his Republican colleagues and party leaders from deciding he’s a liability who needs to be banished from the Capitol. He is telling colleagues he will beat these charges.

How long leadership can sustain this posture is an open question. It was just eight years ago that ethics issues helped hand Democratic Leader Nancy Pelosi the speaker’s gavel. Democrats are already pouncing on Republicans for supporting Grimm, given their zero-tolerance policy. Grimm is the third Republican in six months to be hobbled by scandal. In perhaps the first sign of trouble, the National Republican Congressional Committee pulled Grimm from a May 21 fundraiser benefiting 10 GOP candidates.

Republicans have taken varying tacks with other members in trouble. Boehner privately nudged Florida Rep. Trey Radel — who bought cocaine from an undercover federal agent — to resign. And Louisiana Rep. Vance McAllister is forgoing reelection after being caught in a romantic embrace with his former scheduler. On Tuesday, Cantor urged McAllister to resign now.

Several senior Republicans involved in the party’s campaign apparatus say they won’t spend the money to fight for Grimm’s electoral survival in his pricey New York City district.

“We evaluate races as they develop and look for those where we think there’s an opportunity to win,” NRCC Chair Greg Walden chair said in an interview. When asked whether Grimm could win, Walden carefully repeated his original quote. “Congressman Grimm needs to go make his case to the voters,” the Oregon Republican said.

Grimm has not paid his party dues this cycle, although his leadership PAC — Grass Roots Initiative to Maintain our Majority — gave $25,000 to the House GOP campaign arm. Democrats have already begun calling on the NRCC to give that money back, a traditional attack line against any member in legal or ethical trouble.

In fact, Grimm has been a thorn in the side of the NRCC for months, ignoring its advice to set up a legal defense fund, instead racking up north of $400,000 in legal bills to the D.C. firm Patton Boggs. Setting up a defense fund, Grimm told associates, would be a politically perilous move that could indicate guilt.

On Monday, Grimm “temporarily” resigned his seat on the House Financial Services Committee — a concession that GOP leaders privately saw as non-negotiable. It stripped Democrats of a potential talking point.

Grimm will meet Wednesday with Cantor. The second-term lawmaker will also likely meet with Majority Whip Kevin McCarthy (R-Calif.) at some point.

Grimm, though, has no one-on-one sessions scheduled with Boehner or Walden.

Grimm has quickly tried to settle back into a business-as-usual routine in D.C., showing up at his office Tuesday morning, but skipping the House Republican Conference’s closed meeting at the Capitol Hill Club.

As a member of Congress, Grimm has had to walk a fine line. The House is a chamber where constituencies matter, and Grimm has been a bit of an outsider. He’s a moderate in a chamber with few left in either party, and the only Republican in the New York City congressional delegation. Grimm represents a district that President Barack Obama won by 4 percentage points in 2012, and trends only slightly Republican. Grimm pressed hard for Hurricane Sandy relief and worked to pass a flood insurance bill with members of both parties.

“I’m probably as friendly with him as most guys; he’s sort of a distant guy, a little strange,” said Rep. Peter King of Long Island, the most senior New York Republican. King said he will “still help Michael, I’ll still be a friend.”

King added, “It’s a tough spot to be in, to be under indictment.”

Nudging a member to the door is not a foreign move for either Boehner or Cantor. For example, Cantor called on McAllister to resign Tuesday — just one day after the Louisiana congressman announced he wouldn’t run for reelection following an infidelity scandal — but indicated Grimm was spared his wrath.

Democrats immediately attacked Cantor for the perceived double standard: McAllister should resign after being caught in a romantic embrace with a now former staffer, while Grimm, who faces 20 federal criminal charges, can stay in office.

However, sources familiar with Cantor’s thinking noted that Grimm has asserted his innocence, will have his day in court and has removed himself from the Financial Services Committee. McAllister, meanwhile, admitted wrongdoing, but it involved a subordinate congressional staffer. To Cantor, the situations were not comparable.

Even if Grimm is able to keep Cantor and other party leaders from not calling for his head, he has a laundry list of problems, both legal and political, to confront, and not a lot of time to do it in.

The New York Republican had to put up his house as collateral to pay a$400,000 bond, and he was required to surrender his passport and personal firearm. He will have to check in with U.S. Marshal Pretrial Services as he awaits the start of his trial.